1. Field of the Invention
The present invention relates to a removable closure device for a refrigerator case as well as a fixed or removable screen or canopy for a case of this type.
2. Description of the Prior Art
A refrigerator case or cabinet, especially of the type used for display or sale of food products, such as a chest or display case, is usually of the open type or in other words has an opening which is not separated from the external atmosphere by a material barrier. In a refrigerator case of this type, food products are directly subjected to reheating by radiation of the environmental atmosphere and to reheating by convection of the external atmospheric air. This results in high power consumption in order to produce the cold which is necessary in order to maintain these food products at the temperature prescribed by regulations.
In order to reduce this cold consumption, removable or fixed devices in the form of a cover, canopy or curtain for closing refrigerator cases have already been proposed. These known devices fall into two classes: on the one hand the removable devices which close the opening of a refrigerator case outside selling periods and on the other hand the fixed devices which form a screen against heat radiation and are placed at a distance from the opening opposite to the food products to be preserved. These devices perform the function of a barrier against the heating action of the external atmosphere by convection and/or by radiation. During the period of selling of products, the known devices of the first class are removed, stored or arranged at a predetermined height above said refrigerator case whilst the devices of the second class remain permanently fixed in position.
Known devices in the form of a cover or canopy are usually heavy, cumbersome and costly. Whenever it is necessary to open or close the refrigerator case, considerable time and labor are involved in the handling of these known devices which also require substantial storage space.
One known device in the form of a canopy is usually maintained at a predetermined height above the opening of the refrigerator case in order to protect the latter against heating by radiation but this canopy calls for strong supports which impair the convenience of access to the refrigerator case.
Known devices in the form of a curtain entail the need for an enclosed space for storing them within the refrigerator cases which they are designed to protect. A further point is that the structure of these curtain-type devices is such that cases or cabinets protected by them are not provided with an effective insulating barrier against the external atmosphere.